Love him or hate him, the Antechinus mammal doesn’t care; he’ll still have sex until he physically disintegrates.

The Antechinus, a tiny mouse-like creature, is one of the only semelparous mammals in the world, which means sex is a once-in-a-lifetime thing. For most of their lives they stay nice and chaste until they suddenly stop making sperm, which means they have only a few weeks to reproduce before they die.

That’s when the Antechinus becomes a real lothario. He’ll mate constantly, sometimes for fourteen hours at a time, and do nothing else. His fur falls off, he starts to bleed internally, his whole body becomes infected. But the gangrene doesn’t stop him. The Antechinus will literally keep mating until his body disintegrates and he dies a slow but satisfied death.